


genuinely

by sweetsindle



Category: Kuroshitsuji | Black Butler
Genre: Adoption, Dadbastian, Eventual Happy Ending, Eventually Sebastian adopts him, Fluff and Angst, Fostering to Adopt, Found Family, He fosters Aster who's mother is a crack addict which caused the death of his older bro, He's engaged to Agni who has an adopted son, M/M, Other, Platonic Relationships, Sebastian is dorky goth that does foster care, They get married and their a happy family!, aka Soma, not sebaciel
Language: English
Status: In-Progress
Published: 2020-01-26
Updated: 2020-04-10
Packaged: 2021-02-27 15:01:21
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,162
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22379116
Author URL: https://archiveofourown.org/users/sweetsindle/pseuds/sweetsindle
Summary: ꜰᴏꜱᴛᴇʀ ᴅᴀᴅ ꜱᴇʙᴀꜱᴛɪᴀɴ ᴍɪᴄʜᴀᴇʟɪꜱ ɪꜱ ᴏɴ ᴏɴᴇ ᴏꜰ ᴛᴡᴏ ᴍɪꜱꜱɪᴏɴꜱ - ᴀᴅᴏᴘᴛ ʙᴀʙʏ ᴀꜱᴛᴇʀ, ᴀɴᴅ ᴡɪɴ ᴛʜᴀᴛ ꜱᴘᴇᴄɪᴀʟ ꜱᴏᴍᴇᴏɴᴇ ᴛʜᴀᴛ'ꜱ ʙᴇᴇɴ ɪɴ ʜɪꜱ ꜱɪɢʜᴛꜱ ꜱɪɴᴄᴇ ʜɪɢʜꜱᴄʜᴏᴏʟ!Based on this drabble:https://sweetfacedspare.tumblr.com/post/190423045563/sweets-for-sickness-kuro-birthday-drabble
Relationships: Agni & Soma Asman Kadar, Agni/Sebastian Michaelis, Ciel Phantomhive & Agni, Sebastian Michaelis & Ciel Phantomhive, Sebastian Michaelis & Soma Asman Kadar, Soma Asman Kadar & Ciel Phantomhive
Comments: 16
Kudos: 30





	1. white roses in the playground

**Summary for the Chapter:**

> Sebastian and Aster are in the neighborhood playground, taking a break before heading home from yet another day of daycare, and onto a playdate later that evening with one of baby Aster's friends.
> 
> Their about to leave, after a quick snack when a familiar voice calls out to him.

"What's so interesting, Baby Blue?" 

Twenty-eight-year-old Sebastian asked with a gentle smile, carefully lifting a certain tiny two-year-old baby off the rubber mulch that covered the play area of the neighborhood playground. "You see something interesting?"

Aster, the toddler in his arms, giggled in reply, snuggled deeply into his arms as Sebastian gently rubbed the younger kid's back, as he got up from the bench he had been seated on for the past hour as he watched his foster son play with the other children. 

"Yea..."

"Yeah? What was it?"

The toddler giggled and pointing at a nearby sterling white rose, which just happened to be growing nearby, a soft smile on the child's face. "Pwe'tty! W'ike Miss 'An'wela!" 

"Miss Angela, you mean? From daycare?"

"Yea! She s'owed me how to cwolor m' at art time!"

"She did? Oh, how wonderful - do you have the picture in your backpack?" 

"Mhm-hm! Right there!" Aster pointed, grabbing the blue, rabbit backpack from next to his foster father on the bench with shaky hands, pulling it to the man. He'd try to open it, yanking the zipper as hard as he could, but to no avail - clearly frustrating the small toddler. "Not ow.....penin'! Ma' it op..en....now, Papa!"

Sebastian shook his head, a slight smile forming as he let out a quiet breath. "That's not what we say when we want help, and you know it!" He sat up and smirked. "What do you say, Aster? Do you say 'Open it NOW' or 'Can you please open it'?" 

Giving him a look, the child shook his head. "No! Op...en! I want it _o.....w..pen!"_

"Nope," Sebastian replied, popping the 'P'. "Try again, little man. This time, with your manners. C'mon kid, I know I raised you better than this!"

"No!"

"Yes."

"Nuh-uh, Papa! I'm not gonna say it!"

"And why not?"

_"'Cause!"_

Sebastian sat back, a semi-annoyed groan escaping his lips. He sat there, silent for a second, before turning to the boy, now having an idea. "Well...what would you say if I threw in a cookie for being good if you say it?"

Aster stared at him for a moment. "Wha' kwind...?" the baby asked, cocking his head to the side. "It betta' not be wa'berry...tha's rweally w'hoss..."

"I would I give you strawberry? The last time I made that mistake, you chewed it up at spit it at me - which was, by the way, disgusting-"

The toddler giggled, lazily grabbing a strand of his ashy-blue hair, and twirling it around his little, chubby finger. 

"It's not funny," Sebastian said, his eye twitching in annoyance. "Stop laughing!"

"Bu' it is~ you scr' rweally loud- wike a-"

"A baby? So I sounded like you, Mister Blue?"

"Nu-uh! You swoun'...."

"I sound like what?"

Aster grabbed his backpack, pulling it into Sebastian's lap, before pointing at it. "Op...en!"

"What do you say, little Blue?"

The toddler groaned, and dramatically rolled his eyes, before crossing his tiny arms. "Pw....e...ase."

"I can't hear you~" Sebastian replied in a sing-song voice, laughing as Aster beat his fists into the bench, getting even more frustrated than before. "Can you repeat that?"

"Pwease!"

"What? Did you hear something, Aster? Did someone just say something?"

"Pwease!"

"Is that the lady next to us? Wow I-"

"I SAY, _PWEASE!"_ Aster screamed, tears starting to leak from the blue-haired boy's cerulean eyes. "No one ew'lse is sayin' it! Now pwease, _open!"_

The older man sighed, feeling a twinge of guilt as he awkwardly unzipped the toddler's backpack, handing it to the small child. "Thank you - and I'm sorry," he apologized, sighing softly. "I was just joking. I wasn't trying to make you mad, ok?"

Aster shot Sebastian a look, before digging into the backpack.

While Aster was busy with looking throw the things in his pack to find the drawing Aster had made with his teacher earlier that day, Sebastian reached into the bag that he always carried with him

\- an old messenger bag, from his middle school days - and pulled a few seconds later, a plastic baggie with three, freshly-baked double-chocolate cookies. 

"Hey, Baby Blue?"

"Yea?"

Sebastian held out the bag, just enough so they were in Aster's peripheral vision. It took a few seconds for him to notice, but once he did, it was safe to say that he had successfully made the toddler's day.

The baby giggled excitedly, and just as he was about to reach for them, he paused. 

Looking at his foster father, Aster gave him an awkward smile, setting his tiny hands in his lap. "Can I hwave 'em, Papa?"

"What do you say?"

"Pwease?"

The goth nodded, making the child whoop with pure excitement, snatching the bag from his foster dad's hand, before opening and finally getting to dig in. 

"Mhmm! Papa, their rweally gwoo'! You make em'?" The toddler asked, chewing noisily as cookie crumbs fell from the corners of his mouth. "They don't twaste wike the st' ones!"

"Well, I when I got to work, I only got to work a few hours because someone managed to light the stove on fire, so I got off early! And when I got home, I thought to myself: 'what would make a certain Mister Blue really happy'?"

Swallowing, the child grinned. _"Cwookies!"_

Sebastian laughed and nodded as he gently patted the toddler on the head. "Anyways, you had a drawing you wanted to show me?"

Being reminded of this, Aster's eyes widened, and he nodded, before shoving the other half of his cookie into his mouth. He set the bag down next to him, before digging into his backpack once again, pulling out the drawing he had told Sebastian about earlier, and eagerly shoved it into the older man's hands. "Look! I drew it rweally good! - Miss Anwela hwelped a wot, though!"

"Is that so, Aster?"

"Uh-huh! I drew it jus' for you!"

"You'd do that for me, Blue?" Sebastian asked the baby, clearly flattered by the gesture, smiling like an idiot as he got a good look at the picture. 

It was a drawing of a singular white rose, stem, thorns, and all. The outline was clearly drawn by his teacher, while the coloring was done by little Baby Blue, Aster, (hopefully soon, Michaelis) himself! 

The flower itself was a mixture of an off-white, and violet scribbled messily on top of the grounded-on color (Sebastian himself assumed Aster must have broken the crayon he had been using as a result), while the stem was a light forest green, and the thorns being a gritty storm-grey. 

"You did a great job! I love it - seriously," Sebastian said, grinning, as he pulled the baby close, giving him a small, yet loving hug, just as Aster finished his second cookie. 

"Rweally, Papa?"

"I promise! Why would I lie to you?" Sebastian asked, before getting up and starting to pack both his, and Aster's bags back up - but not before pulling out a powder-blue bunny doll out of his pack and carefully handing it to Aster before finally clicking his bag shut. "You all ready to go? I gotta start making dinner soon - after all, you got a playdate with one of your friends soon!"

Letting out an excited squeal, Aster set his last cookie down and grabbed the doll, hugging the soft thing as hard as he could, giggling adorably. "Yay! Ywou got B'wue back, Papa! I foegot em' before I went to swhool, and I was rweal sad when I saw he wasn't in my bwackpack!"

"I know," Sebastian said, carefully helping Aster put his pack on, before slinging his own back across him. "Miss Angela said you were so upset, that you wouldn't even play with Lizzy and Sieglinde!"

"You mad at me, Papa?" Aster asked, letting out a soft sigh as he looked down to the ground in shame. "I'm rweally sorry...I didn't mean to..."

Sebastian shook his head, just as he scooped his little boy into his arms, carefully resting the toddler on his hip. "No, why would I? Everyone has those days. And anyway, Lizzy is coming over to play while her mommy goes and does some work. You can tell her why you didn't want to play today- I'm sure she'd understand!"

"Rweally?"

"Yup!"

Sebastian smiled, kissing the toddler's head as he started on their way back to their apartment. Just as he set foot on the sidewalk, about ready to turn down the street, a voice called out after him.

_"Sebastian! - Sebastian, is that you?"_


	2. meeting

**Summary for the Chapter:**

> After thinking he'd never get to see him again - here Agni was after what, 8 years? And with an adoptive child as well? How curious! 
> 
> Maybe there's a chance to meet up - maybe have his son meet his own, while they're at it!

"I- for fu-" Sebastian cut himself off, midsentence, just as he realized what he was about to say - in front of his toddler son, no less! _'Argh, goddammit - remember Sebastian, remember! No swearing when Aster's around! Can't have him catching on!'_ he thought, cursing himself out in pure embarrassment, flushing a rather lovely shade of carnation pink. 

"Papa...?" Aster asked, cocking his head to the side as he clutched his rabbit tightly. "Who he...?"

"Sebastian, yes, hello!" The man a bit away, several, several feet away from the two called, with a bright smile on his face. "It's me, Agni! It's been so long since I've last seen you!"

"Oh my God, It's him!" Sebastian found himself saying aloud, blushing even harder as he whipped around, confirming his suspicion. "Agni! I haven't seen you since graduation! Where have you been?!"

"Where have I been, Sebastian?" The man - Agni, started, smiling brightly as he walked forward, his face, as well as a boy with plum-colored hair that looked no older than six next to him? Coming into view. "You said we'd hang out a few days after graduation! Whatever happened?"

"Papa! Who he!" Aster asked again, this time sounding a bit whiny as he got a better look at the strange man in front of them. "Who heeeeeeee?!"

"Ah! Aster, Aster! Please calm down!" Sebastian asked, his eyes widening in complete and utter embarrassment. _'Out of all the times to be whiny, he picks now?! Oh God, please don't cry, please, don't cry, please please PLEASE don't throw a tantrum I-'_

Agni grinned broadly, finally making it to the two, the plum-haired boy that Sebastian had noticed earlier, in tow. "Ah! Who's this?" he asked, playfully pointing to the toddler in Sebastian's arms. "What's your name? My name is Agni! I knew your Papa back awhile ago! And this-" he put a gentle hand on the boy next to him, before lifting him up as well, causing a fit of a giggle from the older child. "Is my son, Soma! He's six!"

"Awster! Papa say...uh...I..." Aster froze, clearly lost on the 'How old are you?' question.

Sebastian rolled his eyes, chuckling softly, giving Aster a loving squeeze. "He's two. About to turn three in what, six months? You gonna have a party, Blue?"

Aster looked to his father and gave him a sharp shake. "No! Hate!"

"He hates parties? That's a first!" Agni said, laughing softly. "Soma loves parties! He always has an excuse to have one!"

"Fun!" Soma exclaimed, giggling, just as Agni put him down. "I like havin' em'! We had one on Satur'ay! We drank cocoa and watched Frozen!"

"Oh, really? That sounds like fun!" Sebastian said with a slight smile. "If only a certain Mister Blue would willingly sit through movies-"

"Bo'ing!" Aster replied, eyes now all on Soma. He clung to Sebastian at an awkward angle, trying to get a better look.

"Boring? I thought everyone loved movies!"

"Not him - he much rather read a book any day - or play with his toys. Whenever I put on a movie, he usually just leaves and goes to the playroom!"

"Ah! So books are his favorite? If only Soma had that interest outside of school! He's very, very smart, and he can get through his subjects like it's nothing, but no matter what, I can never, ever, get him to read outside of his lessons!"

"Really?"

"Yes! It's crazy! _Let me tell you..."_

As the two adults talked, Aster (somehow) had managed to get out of Sebastian's arms completely, and back on the ground where he finally got a chance to be with Soma, face to face. 

He looked at the older kid, clearly interested, as he gently held his rabbit in his arms. "W'oma? You name?"

"No! Soma!"

"W'oma?"

"Soma!"

"Huhhh..." The toddler thought for a second, freezing like a statue in the process. "S....a....S....o....ma..."

"Yes! Y'said it right!"

The younger child's eyes widened as he broke into a smile, clearly proud of himself. "Say w'ight?!"

"Said right!"

"Yay!" Aster cheered, giggling, giving his rabbit a tight hug. "Happy! T'day I say two ha' words! S.....o.....ma! And pwease! Hard! But I say em'!"

"Words are fun! I like sayin' em'! 'Specially 'cause they're weird! - And they mean so many things!"

"Rwea'y?"

"Uh-huh! I can teach you!"

"Twe' me?"

"Uh-huh!"

"Rwe'y?!"

"Yeah!"

"Yay!" Aster grinned, clearly very excited to learn more...despite new words being super hard. And what had happened earlier with the whole backpack debacle hadn't been his favorite...but still! "Wi' wearnin'! Papa hwep me wearn! He teaches me numba!"

"Numbers? I know my numbers!"

"Rwe'y? How much?"

"To a hun'dred!"

"Hwu....un...dred...?"

"Hundred!"

"Ooooh! New word! It bw'g!"

"Aster! ASTER! WHERE DID YOU-" Sebastian froze, calming down as soon as he noticed his little son nearby, talking to who he had recently learned from Agni was Soma, his six-year-old adopted son. "I...Oh, jeez. How did you get out, Aster?"

The toddler looked up to his father and giggled softly. "G' out! 'Alk wiv' S....o....ma! He know words! Numbas too!"

"Oh, really?" Sebastian asked with a gentle smirk, resting a hand on his hip. "Words? And numbers? As good as you, Mister Blue?"

"Nu-uh!" Aster replied, shaking his head. " Betta'! Wanna be like em', Papa!"

"Like me?" Soma asked the toddler, a bright smile appearing on his already-cheery face. "Really?!"

"Yea!" Aster grinned, grabbing Soma's hand. "Wanna!"

"Yay!" Soma cheered, bending down a tiny bit, enveloping the toddler in a hug - and Aster...allowed it? 

_'This is a first,'_ Sebastian thought, clearly surprised by Aster's acceptance. Usually, whenever someone tried touching him (it could literally be ANYONE), he'd throw a tantrum - cry, scream, kick - the works! 

But here, he was...letting Soma hug him? Perhaps he actually liked him? This was so strange! He seldom even let Lizzy hug him - and Aster knew her since he was an infant! How on earth was Soma different? 

"Aster! We're friends now!" Soma declared, matter-of-factly. "I'll teach you ev'thing! You'll be my little bro'tha!" he told the baby, giving him a gentle pat on the top of his ash-blue hair.

"Fr....iends...? Bro...tha?" 

"Mhm-hm!"

"Wha' that?"

"I'm sure you have friends, Aster. Like Lizzy - your father mentioned her! You two sound like wonderful friends," Agni said, suddenly joining the conversation with a warm smile, clearly endeared by the site. "And a brother...a brother is like a friend, but much, much more special. Their someone that you have a bond like any other, and can understand each other better than anyone else! You always have time for them, and they're wonderful. You'll have time for them, and they always have time for you!"

"Rwe'y?" Aster asked, soaking up all the knowledge like a wet sponge. "Tha' sounds...mhm..." the younger child struggled to find the words and tried for a bit...until he finally gave up. "Uh...I dunno! Want one!"

"You want one, Blue?"

"Uh-huh! S...om...a! He b'wotha!" Aster said, pointing directly at the golden-eyed boy in front of him. "B'wotha!"

"He's your brother, Mister Blue?"

"Yea! B'wotha!" 

Both Agni and Sebastian shared a smile, letting out a laugh while the two little boys held each other in an embrace, celebrating their newfound bond. 

"It's settled! You're my little brother!" Soma giggled, giving Aster a big, wet kiss on the top of his head, making the younger give him a look.

"Ew!"

"Heeeeeeey, hey- be nice, Blue!" Sebastian grinned, just as he scooped Aster up, and gave him a kiss on the cheek. "So, let me get this straight -" he said, turning back to Agni, his heart starting to race. "You're free, and you wanna hang out with Aster and me, eh?"

Agni nodded. "If only you want to! - I wouldn't want to intrude on anything. Do you have anything going on?"

"Well, Lizzy is coming over for a playdate until like what...eleven? It's fine, though. Aster and Soma have become fast friends, and I'm sure that Soma will befriend Lizzy in no time - or Lizzy will, whatever comes first, haha! While they play, we can hang out! I'll make dinner and everything. It'll be tater tots and pizza, but hey! Free dinner! And you get to be irritated by me! What could be better?" Sebastian asked in a joking tone, feeling himself getting a little bit more and more ansty by the second. _'Oh God, what if I made this weird?! What if he says- wait, wasn't he the one who? What at I on I swear to God-'_

"If you don't mind, sure thing! I'm sure that Soma would love to play with Aster, as well as make another new friend - and it'd be lovely to get to talk to you again."

"I mean...only if you want." Sebastian smiled, hitching his almost-fallen messenger bag back up his shoulder. "My apartment is just down there-" he said, pointing down the street. "Mine and Blue's number is 305! How does 6:30 sound?"

"Perfect!" Agni nodded. "Can I see your phone?"

"Uh...sure?" Sebastian agreed, awkwardly pulling his brand new iPhone from his back pocket, and handing it to him. "What do you need it for?"

Agni made several taps on the screen before handing it back, his only reply is a smile. "I'll see you and Aster soon! It was nice talking!" he said, giving Sebastian a quick hug before giving Aster a little wave, and gently taking ahold of his son's hand, and walking off.

Sebastian stood there for a while, almost in awe, holding Aster securely in arms for what seemed like an eternity.

He broke into a stupid smile and turning a heel, starting the walk back to his apartment.

"You smwin' weird, Papa."

"Am I, Blue?"

"Uh-huh!"

Walking to the building, getting inside, and being greeted by the receptionist, he took the elevator, and before he knew it, they were both back home. Just as he opened the door, Aster asked him a question.

"Wike em'?"

"Hm...?"

"Ag....ni."

"Why do you ask, Blue?"

"Wook at em' funny. Wike how Awunnie Gw'lle wooks at Uncle Oth'llo!"

Sebastian sighed, stepping inside their home before closing the door and giving his son a look. "Oh God...is it that obvious?!"

"Uh-huh!"

"That's it...I'm going to die. Aster, plan my funeral."

"Wha'?! Papa, _no!"_


End file.
